Even full upgrades, you need to circle enemies 90% of the time. No matter what you do, if you try to trade blows with a swarm of enemies you WILL DIE. Honestly it gets kind of boring. After the first three hours of circling and spamming abilities, I finally realized why completing the game got a hard badge. The REAL challenge is how long you can circle before you break and try to take out all the enemies at once and get yourself killed.
What is that shark made of?!?! it brought stacks of shipping containers down on it's head, was in the middle of countless explosions, and was able to clamp it's teeth down on a speeding asteroid AND bring it down into the water AND survive Earth exploding AND survived the vacuum of space.
(insert slow sarcastic clapping)
 "Idleplex"){kind=icon}
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 "Clear Vision"){kind=icon}
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 "Frantic Frigates"){kind=icon}
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 "Nuclear Outrun"){kind=icon}
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 "New York Shark"){kind=icon}